Closed fluid operated pumping system with parallel and concentric tubings



Oct. 24, 1961 c. J. COBERLY CLOSED FLUID OPERATED PUMPING SYSTEM WITH PARALLEL AND CONCENTRIC TUBINGS 3 Sheets-Sheet 1 Filed July 6, 1959 M N EM M 4 3 f M E j 3 i 5 w. P C m M a s Q 5 2 wv /.K E 5 a s E w i E Q m W E L I a 4 K W 5, a Q 3 Z MW f 0/7 Oct. 24, 1961 c. J. COBERLY CLOSED FLUID OPERATED PUMPING SYSTEM WITH PARALLEL AND CONCENTRIC TUBINGS 3 Sheets-Sheet 3 Filed July 6, 1959 aLfiENCE (I toss/a4.

.57 1 /15 #rram/L ys ,HZQQ/} ja/Ecwgflassezz 5165M United States Patent f CLOSED FLUID OPERATED PUMPING SYSTEM WITH PARALLEL AND CONCENTRKC TUBINGS Clarence J. Coberly, San Marino, Calif, assignor to Kobe,

Inc., Huntington Park, Calif., a corporation of California Filed July 6, 1959, Ser. No. 825,051 Claims. (Cl. 10346) The present invention relates in general to fluid operated pumping systems for wells and more particularly to a pumping system of this type for use in a well having a reduced bottom hole diameter.

For reasons well known in the art it is advantageous to employ a tubing system for conveying operating fluid downwardly to and upwardly from the pump and for conveying production fluid upwardly from the pump which comprises tubings set in the well in parallel or side-by-side relation as opposed to a concentric relation. However where the bottom hole diameter of the well is reduced as by the use of a casing of reduced diameter at the bottom of the well or the use of a perforated liner at the bottom 'of the well having a diameter less than that of the casing there frequently is not enough space available at the bottom of the well for a parallel tubing system. My Patent No. 2,676,546 granted April 27, 1954, solves the foregoing problem in an open system, wherein the spent operating fluid and the production fluid are mixed and returned through a single, production tubing, by employing a parallel tubing system down to the level at which the reduced bottom hole diameter makes a downward continuation of the parallel system impossible, and by employing a concentric tubing system -below such level. While my aforementioned patent provides a solution for an open system, such a system has the disadvantage of requiring constant replacement of the operating fluid used to actuate the pump since the spent operating fluid is mixed with the production fluid from the well, which results in obvious disadvantages.

A primary object of the invention is to provide a closed fluid operated pumping system, wherein the spent operating fluid is returned to the surface independently of the production fluid from the well, which utilizes parallel, i.e., side-by-side, operating fluid supply, operating fluid return and production tubings down to the level of well diameter reduction, and a concentric system of operating fluid supply, operating fluid return and production tubings below such level.-

More particularly, a primary object of the invention is to provide a fluid operated pumping system which includes upper supply, return and production tubings set in the well in side-by-side relation; lower supply, return and production tubings in the well below the upper tubings and in concentric relation; and means interconnecting the lower ends of the upper tubings and the upper ends of the lower tubings and providing a supply passage connecting the lower supply tubing in fluid communication with the upper supply tubing, a return passage connecting the lower return tubing influid communication with the upper return tubing, and a production passage connecting the lower production tubing in fluid communication with the upper production tubing.

An important object of the invention is to provide a fluid operated pumping system of the foregoing nature which includes a free fluid operated pump assembly hydraulically movable between the surface and an operating position in the well through one of the parallel upper tubings and the outermost of the concentric lower tubings, which tubings are in axial alignment.

Another important object is to provide a fluid operated free pump assembly which includes a fluid operated pump and which includes the intermediate and inner Patented Oct. 24., 1961 ones of the concentric lower tubings, the intermediate and inner lower tubings thus being hydraulically movable between the surface and the operating position of the pump assembly in the well along with the pump itself.

A further important object is to provide a pumping system which includes first coupling means interconnecting the lower ends of the upper tubings and the upper end of the outer lower tubing, a second coupling means interconnecting the upper ends of the intermediate and inner lower tubings and registering with the first coupling means when the pump assembly is in its operating position and passage means formed in the two coupling means mentioned for connecting the lower supply tubing in fluid communication with the upper supply tubing, the lower return tubing in fluid communication with the upper return tubing and the lower production tubing in fluid communication with the upper production tubing when the pump assembly is in its' operating position.

Still another important object of the invention is to provide a fluid operated pumping system of the foregoing nature wherein the upper and lower tubings through which the free pump assembly is movable, i.e., the outer lower tubing and the upper tubing aligned therewith, respectively constitute the upper and lower production tubings and are respectively larger than the others of the upper and lower tubings. With this construction, the largest tubings are utilized as the production tubings to minimize friction losses in the production fluid flowing upwardly from the pump to the surface, which is an important feature.

Another object of the invention is to provide a fluid operated pumping system of the character hereinbefore outlined which includes an axial passage through the fluid operated pump from the lower supply tubing to the exterior of the pump adjacent the lower end thereof, valve means normally closing such axial passage, and pressure responsive means exposed to the interior of the lower production tubing for opening the valve means to permit the application of operating fluid pressure to the lower end of the pump for the purpose of moving the pump assembly upwardly out of its operating position.

With this construction, the pump assembly remains in its operating position until the pressure in the production tubing is elevated above normal suiflciently to open the valve means mentioned, whereupon the operating fluid pressure may be utilized to move the pump assembly upwardly out of its operating position.

The foregoing objects, advantages, features and results of the present invention, together with various other objects, advantages, features and results thereof which will be evident to those skilled in the fluid operated pumping art in the light of this disclosure, may be attained with the exemplary embodiment of the invention described in detail hereinafter and illustrated in the accompanying drawings, wherein:

FIG. 1 is a view, partially in elevation and partially in vertical section and on a reduced scale, illustrating a fluid operated pumping system which embodies the invention as installed in a well;

FIG. 2 is a horizontal sectional view taken along the arrowed line 2-2 of FIG. 1;

FIG. 3 is a fragmentary vertical sectional view taken along the arrowed lines 3-3 of FIGS. 1 and 2;

FIG. 4 is a fragmentary vertical sectional view taken along the arrowed line 4-4 of FIG. 2 and at the same levelv as FIG. 3;

FIGS. 5, 6 and 7 are fragmentary vertical sectional views respectively taken along the arrowed lines 55, 66 and 7-7 of FIG. 1; and

FIG. 8 is a horizontal sectional view taken along the arrowed line 8--8 of FIG. 5.

Referring particularly to FIG. 1 of the drawings, the numeral 18' designates a well bore having a nonproductive upper zone 12 of relatively large diameter and having a productive lower or bottom hole zone 14 of reduced diameter, the upper zone containing a casing 16 and the lower zone containing a perforated line 18 which is suitably connected at its upper end to the lower end of the casing.

Suspended from a casing head 21 at the upper end of the casing 16 and extending downwardly in the casing in parallel or side-by-side relation are operating fluid supply, spent operating fluid return and production tubings 22, 24 and 26, respectively. The supply, return and production tubings 22, 24 and 26 are connected above the casing head 20 to a selector valve means 28 having supply, return and production lines 32, 34 and 36 connected thereto. In normal operation, the supply, return and production tubings 22, 24 and 26 are connected in fluid communication with the supply, return and production lines 32, 34 and 36, respectively. However, to perform certain functions which will be described hereinafter, the selector valve means 28, which is operable by a handle 38, establishes other relationships between the tubings 22, 24 and 26 and the lines 32, 34 and 36.

' The lower ends of the supply, return and production tubings 22, 24 and 26 are interconnected by a coupling means or sealing collar 48 disposed within the casing 16 adjacent the lower end thereof and just above the liner 18, the diameter of the liner being insuflicient to receive the parallel supply, return and production tubings. Connected to the sealing collar 41 in axial alignment with the upper production tubing 26 is the upper end of a lower production tubing 42 which extends downwardly into the liner 18 and which has a bottom shoe 44 connected to the lower end thereof. The length of the lower production tubing 42 is sufficient to locate the bottom shoe 44 below the level of well fluid in the liner 18, the length of the lower production tubing being as much as several hundred feet, or more.

Referring to FIG. 7, the bottom shoe 44 is provided therein with an annular seat 46 for a standing valve assembly 48 which, as is well known in the art, permits upward flow of well fluid from the well, but prevents downward flow back into the well. The standing valve assembly 48 is provided at its upper end with a pump seat 50 for the lower end of a fluid operated pump 52. This pump may have any suitable construction, such as that of my Patent No. 2,311,157, granted February 16, 1943, the disclosure of such patent being incorporated herein by reference, as are the disclosures of various other patents mentioned and to be mentioned herein. Consequently, a detailed description of the pump 52 is unnecessary.

Briefly, the fluid operated pump 52 includes a pump section 54 which includes a pump cylinder and a pump piston, not shown, and which includes a well fluid inlet 56 communicating with the standing valve assembly 48 and a production fluid outlet 58, FIG. 6, communicating with the lower production tubing 42. The fluid operated pump 52 also includes above the pump section 54 a fluid operated engine section 60 comprising an engine cylinder and an engine piston, not shown, and an engine valve 61, the engine section having an intake 62 for operating fluid under pressure and an exhaust 64 for spent operating fluid, as shown in FIG. 6.

The fluid operated pump 52 forms the lower end of a fluid operated free pump assembly 66 which is hydraulically movable through the upper and lower production tubings 26 and 42 between the surface and an operating position wherein the lower end of the pump, which comprises the well fluid inlet 56, is seated on the pump seat 50 provided by the standing valve assembly 48. In its operating position, the fluid operated pump 52 is entirely below the junction of the upper supply, return and production tubings 22, 24 and 26 and the lower production tubing 42, which junction is formed by the coupling means or sealing collar 48, and may be several hundred feet, or more, therebelow.

Considering the free pump assembly 66 in more detail, it includes concentric lower supply and return tubings 68 and 70 which are concentrically disposed within the lower production tubing 42 when the free pump assembly is 1n its operating position, the lower production tubing 42 thus being the outermost of the three concentric tubings. Preferably, the lower supply tubing 68 is the innermost of the three concentric lower tubings and the lower return tubing 70 occupies an intermediate position.

As shown in FIG. 6, the upper end of the fluid operated pump 52 and the lower ends of the lower supply and return tubings 68 and 70 are interconnected by a coupling means 72 which provides a passage means 74 connecting the lower supply tubing 68 and the engine section intake 62 in fluid communication, and which provides a passage means 76 interconnecting the engine section exhaust 64 and the lower return tubing 70 in fluid communication, or, more accurately, interconnecting the engine section exhaust 64 and the annulus between the lower supply and return tubings 68 and 70 in fluid communication. The annulus just mentioned is maintained by ribs 78 on the lower supply tubing 68 and engaging the lower return tubing 70.

The lower supply and return tubings 68 and 70 are made up in sections connected by coupling means 80 one of which is shown in FIG. 5 of the drawings. Each coupling means 80 includes an insert 82 disposed between adjacent sections of the lower supply and return tubings 68, such insert having a passage means 84 which interconnects the two sections of the lower supply tubing 68 and having a passage means 86 which interconnects the two sections of the lower return tubing 70. Each coupling means 80 also includes a coupling 88 threadedly engaging the two adjacent sections of the lower return tubing 70.

Turning now to FIG. 3 of the drawings, the upper ends of the lower supply and return tubings 68 and 70 are interconnected by a coupling means 90 which is disposed within the coupling means or sealing collar 40 when the free pump assembly 66 is in its operating position. Connected to the upper end of the coupling means 90 is a packer mandrel 92 carrying downwardly facing packer cups 94 which are disposed in enlargements 96 of the upper production tubing 26 when the free pump assembly 66 is in its operating position so as to permit upward flow of the production fluid discharged by the pump section 54 of the pump 52. However, upon slight upward movement of the free pump assembly 66, which is produced in a manner to be described, the packer cups 94 make fluid tight seals with the upper production tubing ,26 to move the free pump assembly 66 upwardly through the upper production tubing to the surface.

Considering the manner in which the upper supply, return and production tubings 22, 24 and 26 are connected in fluid communication with the lower supply, return and production tubings 68, 70 and 42, respectively, when the free pump assembly 66 is in its operating position, the two coupling means 40 and 90 provide a supply passage 98 connecting the lower supply tubing 68 in fluid communication with the upper supply tubing 22, a return passage 100 connecting the lower return tubing 70 in fluid communication with the upper return tubing 24, and a production passage 102 connecting the lower production tubing 42 in fluid communication with the upper production tubing 26. The passages 98, 100 and 102 will now be considered in detail in the order presented.

Considering the supply passage 98, it includes a. bore 104 in the sealing collar 40 into the upper end of which the lower end of the supply tubing 22 is threaded. The lower end of the bore 184 communicates with radial ports 1% in .the sealing collar 40 which communicate with an internal annular channel 108 in the sealing collar.

Within the sealing collar 40 is a liner 110 having radial poifts' 112 which communicate with the annular channel 108 and which communicate with an internal annular channel 114 in the liner. When the free pump assembly 66 is its operating position, the internal annular chan nel 114 in the liner 110 communicates with an external annular channel 116 in the coupling means 90, the chanml 116 being isolated by two of three O-ring's, or the like, 118 carried by the coupling means 90 and engage= able with the liner 110. The coupling means 96 is provided with radial ports 120 which connect the external annular channel 116 therein to an axial passage 122 leading downwardly to and communicating with the upper end of the lower supply tubing 68. Thus, when the free pump assembly 66 is in its operating position, fluid com-- munication between the upper supply tubing 22 and the lower supply tubing 68 is established through the coupling means 40 and 90 in the manner just described.

The return passage 100 is similar to the supply passage 98 and includes a bore 124 into the upper end of which the lower end of the upper return tubing 24 is threaded, radial ports 126 and an internal annular channel 128 in the sealing collar 40, radial ports 132 and an internal annular channel 134 in the liner 110, and an external annular channel 136, radial ports 140 and an annular passage 142 in the coupling means 21 the external annular channel136 being isolated by two of the O-r'ings 118; Thus, fluid communication between the upper return tubing 24 and the lower return tubing 70 is established through the coupling means 48 and 90 when the free pump assembly 66 is in its operating position;

The production passage 102 includes a vertical bore 144 in the sealing collar 40 offset to one side of the liner 110, and includes radial ports 146 and 148 formed in the sealing collar 40 and respectively connecting the upper and lower ends of the bore 144 to internal annular channels 150 and 152 formed in the sealing collar 40 and respectively communicating with the lower end of the upper production tubing 26 and the upper end of the lower production tubing 42. The uppermost and lowermost of the O-rings 118 on the coupling means 90 isolate the annular channels 158 and 152 in the sealing collar or coupling means 40. Thus, the bore 144, the ports 146 and 148 and the annular channels 150 and 152 constitute the production passage 102 interconnecting the upper production tubing 26 and the lower production tubing 42 in fluid communication when the free pump assembly 66 is in its operating position.

Referring to FIG. 7 of the drawings, the fluid operated pump 52 is provided with a balance tube 154 the normal function of which is explained in the aforementioned Patent No. 2,311,157. As disclosed in detail in my Patent No. 2,851,954, granted September 16, 1958, the balance tube 154 forms part of an axial passage 156- which extends downwardly through the pump 52 from the operating fluid intake 62 at the upper end of the pump to the exterior of the pump adjacent the lower end thereof. The lower end of the axial passage 156, which is formed by radial ports 158 in the housing of the pump 52, com-- municates with the interior of the bottom shoe 44'abo've the pump seat 50, the interior of the bottom shoe being isolated from the lower production tubing 42 by an O- ring 160 on the pump and engageable with a liner 162 in the bottom shoe. The axial passage 156 is normally closed by a valve means 164 which is movable into an open position by a piston 166 in response to a predetermined pressure in the lower production tubing 42, the piston 166 having an end 168 exposed to the lower production tubing. When the predetermined pressure in the lower production tubing 42 is developed in a manner to be described, the piston 166 opens the valve means 164 so that operating fluid from the lower supply tubing 68 may flow downwardly through the axial passage 156 to act upwardly on a downwardly-facing annular area 170 of the pump 52 to move the pump upwardly, as hereinafter described in more detail. Since the axial passage 156,

the valve means 164, the piston 166', and other elements associated with these elements, are fully described in my Patent No. 2,851,954, a further description herein is unnecessary.

Operation Considering the over-all operation of the invention, it will be assumed that the fixed portion of the tubing systern, including the upper supply, return and production tubings 22, 24 and 26 and the lower production tubing 42, has been set in the well and that the standing valve assembly 48 is in place on the annular seat 46. With the foregoing conditions obtaining, a closure 172 at the upper end of the upper production tubing 26 is removed and the free pump assembly 66 is inserted into the upper production tubing, the valve means 164 being in its closed position. The closure 172 is then replaced.

The foregoing accomplished, the handle 38 of the selec tor valve means 28 is moved to a position such that the selector valve means connects the upper production tubing 26 above the free pump assembly 66 to the supply line 32, the selector valve means simultaneously connecting the upper supply and return tubings 22 and 24 to the production line 36. With the selector valve means 28 set in this position, operating fluid under pressure from the supply line 32 is introduced into the upper production tubing 26 above the free pump assembly 66 to move the latter downwardly through the upper production tubing and into the lower production tubing 42, any fluid below the free pump assembly being displaced upwardly through V the upper supply and return tubings 22 and 24, since the standing valve assembly 48 prevents downward flow into the well, and being disposed of through the production line 36. Ultimately, the lower end of the pump 52 seats on the pump seat 50, any fluid trapped below the O-ring 160 when it enters the liner 162 flowing into the well fluid inlet 56 of the pump and being disposed of by the pump itself in the manner set forth in my Patent No. 2,851,954. It will be understood that while the free pump assembly 66 is being run in and seated in the foregoing manner, the applied pressure is maintained at a value less than that'required tor the piston 166 to open the valve means 164 so that this valve means remains closed.

Once the free pump assembly 66 has been seated, the coupling means 40 and establish fluid communication between the upper supply, return and production tubings '22, 24 and 26 and the lower supply, return and production tubings 68, 70 and 42, respectively, through the supply, return and production passages 98, and 102, respectively, in the manner hereinbefore set forth. The selector valve means 28 is now set in a position such as to connect the upper supply, return and production tubings 22, 24 and 26 to the supply, return and production lines 32, 34 and 36, respectively, whereupon the engine section 60 of the pump 52 operates in the conventional manner for fluid operated pumps to cause the pump section 54 to pump well fluid from the well upwardly, as production fluid, through the lower production tubing 42, the production passage 102 and the upper production tubing 26 into the production line 36 leading to a suitable point of storage or the like.

When it is desired to remove the free pump assembly 66 from the well, the selector valve means 28 is set in a position such that it connects the supply line 32 to the upper production tubing 26. The fluid pressure in the upper production tubing 26, the production passage 182 and the lower production tubing 42 thus builds up, as operating fluid under pressure is delivered to the upper production tubing from the supply line 32, until, ultimately, the pressure applied to the end 168 of the piston 166 is sufiicient to unseat the valve means 164 and move it to the left, as viewed in FIG. 7 of the drawings, into its open position. This results in connecting the lower supply tubing 68 to the annular area at the lower end o'f th'e pump 52 byway of the axial passage 156.

The selector valve means 28 is then set in a position to connect the upper supply tubing 22 to the supply line 32 and the upper production tubing 26 to the production line 36, the upper return tubing 24 also preferably being connected to the supply line 32 at this stage. The operating fluid pressure applied to the upper tubing 22 is conveyed downwardly through the upper supply tubing, the supply passage 98, the lower supply tubing 68 and the axial passage 156 and isapplied to the annular area 170 at the lower end of the pump 52 to unseat the pump. As soon as the pump 52 unseats, the standing valve in the standing valve assembly 48 closes and the operating fluid pressure acts upwardly on the entire cross sectional area of the pump to move it upwardly. The spacing between the uppermost and intermediate ones of the rings 118 on the coupling means 90 is suflicient to maintain communication between the upper supply tubing 22 and the lower end of the pump 52 until the lowermost one of the O-rings 118 has cleared the internal annular channel 134 in the liner 110. Consequently, when the O-ring 160 adjacent the lower end of the pump 52 clears the liner 162, the operating fluid pressure applied to the upper return tubing 24 acts upwardly on the entire cross sectional area of the pump to continue the upward movement of the pump. Ultimately, the lowermost of the O-rings 118 clears the internal annular channel 114 in the liner 110 and, when this occurs, operating fluidfor moving the pump 52 upwardly may be supplied through both the upper supply and return tubings 22 and 24, or through either one of them. It will be understood that by the time all of the O-rings 118 clear the liner 110, the Packet cups 94 have cleared the enlargements 96 so that the operating fluid introduced through the upper supply tubing 22 and/or the upper return tubing 24 acts on the packer cups to continue the upward movement of the free pump assembly 66. Ultimately, the free pump assembly reaches the surface and may be engaged and held by a pump catcher, not shown, carried by the closure 172.

Thus, the present invention provides a fluid operated pumping system which permits the use of parallel or sideby-side tubings, in a closed system, down to a depth at which a reduction in diameter makes a downward continuation of the parallel system impossible, without, how ever, requiring a concentric tubing system all the way from the surface. Also, the invention provides a fluid operated pumping system wherein the tubings through which the tree pump assembly is circulated, which are the largest tubings'in the system, are utilized as the production tubings to minimize friction losses in the production flow.

Although an exemplary embodiment of the invention has been disclosed herein for purposes of illustration, it will be understood that various changes, modifications and substitutions may be incorporated in such embodiment without departing from the spirit of the invention as defined by the claims which follow.

I claim:

1. In a fluid operated pumping system for a well, the combination of: upper supply, return and production tubings set in the well in side-by-side relation; an outer lower tubing set in the well below saidupper tubings and aligned with and forming a downward continuation of one of said upper tubings; intermediate and inner lower tubings disposed within and concentric with said outer lower tubing, one of said lower tubings being a lower supply tubing, another of said lower tubings being a lower return tubing, and the third of said lower tubings being a lower production tubing; and means interconnecting the lower ends of said upper tubings and the upper ends of said lower tubings for connecting said lower supply tubing in fluid communication with said upper supply tubing, said lower return tubing in fluid communication with said upper return tubing and said lower production tubing in fluid communication with said upper production tubing.

2. In a fluid operated pumping system for a well, the

combination of: upper supply, return andproduction tubings set in the well in side-by-side relation; an outer lower tubing set in the well below said upper tubings and aligned with and forming a downward continuation of said upper production tubing, said outer lower tubing being a lower production tubing; intermediate and inner lower tubings disposed within and concentric with said lower production tubing, said intermediate lower tubing being a lower return tubing and said inner lower tubing being a lower supply tubing; and means interconnecting the lower ends of said upper tubings and the upper ends of said lower tubings for connecting said lower supply tubing in fluid communication with said upper supply tubing, said lower return tubing in fluid communication with said upper return tubing and said lower production tubing in fluid communication with said upper production tubing. 3. In a fluid operated pumping system for a well, the

combination of: upper supply, return and production tubings set in the well in side-by-side relation; an outer lower tubing set in the well below said upper tubings and aligned with and forming a downward continuation of one of said upper tubings; intermediate and inner lower tub ings disposed within and concentric with said outer lower tubing, one of said lower tubings being a lower supply tubing, another of said lower tubings being a lower return tubing, and the third of said lower tubings being a lower production tubing; coupling means interconnecting the lower ends of said upper tubings and the upper end of said outer lower tubing; coupling means interconnecting the upper ends of said intermediate and inner lower tubings; and passage means formed in said coupling means for connecting said lower supply tubing in fluid communication with said upper supply tubing, said lower return tubing in fluid communication with said upper return tubing and said lower production tubing in fluid communication with said upper production tubing.

4. In a fluid operated pumping system for a well, the combination of: upper supply, return and production tubings set in the well in side-by-side relation; an outer lower tubing set in the well below said upper tubings and aligned with and forming a downward continuation of one of said upper tubings; a pump seat at the lower end I of said outer lower tubing and communicating with the well; a fluid operated pump assembly movable downwardly through said one upper tubing into said outer lowertubing and having a fluid operated pump at its lower end, said pump having a well fluid inlet at its lower end which is seatable on said pump seat in fluid communication with the well, said pump assembly including intermediate and inner lower tubings disposed within and concentric with said outer lower tubing when said well fluid inlet is seated on said pump seat, one of said lower tubings being a lower supply tubing, another of said lower tubings being a lower return tubing, and the third of said lower tubings being a lower production tubing, said pump having an operating fluid intake, a spent operating fluid exhaust and a production fluid outlet which communicate with said lower supply tubing, said lower return tubing and said lower production tubing, respectively, when said well Lfluid inlet is seated on said pump seat; and means interconnecting the lower ends of said upper tubings and the upper end of said outer lower tubing and interconnecting the upper ends of said intermediate and inner lower tubings for connecting said lower supply tubing in fluid communication with said upper supply tubing, said lower return tubing in fluid communication with said upper return tubing and said lower production tubing in fluid communication with said upper production tubing when said well fluid inlet is seated on said pump seat.

5. In a fluid operated pumping system for a well, the combination of: upper supply, return and production tubings set in the well in side-by-side relation; an outer lower tubing set in the well below said upper tubings and aligned with and forming a downward continuation of one of said upper tubings; a pump seat at the lower end of said outer lower tubing and communicating with the well; a fluid operated pump assembly movable downwardly through said one upper tubing into said outer lower tubing and having a fluid operated pump at its lower end, said pump having a well fluid inlet at its lower end which is seatable on said pump seat in fluid communication with the well, said pump assembly including intermediate and inner lower tubings disposed within and concentric with said outer lower tubing when said well fluid inlet is seated on said pump seat, one of said lower tubings being a lower supply tubing, another of said lower tubings being a lower return tubing, and the third of said lower tubings being a lower production tubing, said pump having an operating fluid intake, a spent operating fluid exhaust and a production fluid outlet which communicate with said lower supply tubing, said lower return tubing and said lower production tubing, respectively, when said well fluid inlet is seated on said pump seat; coupling means interconnecting the lower ends of said upper tubings and the upper end of said outer lower tubing; another coupling means interconnecting the upper ends of said intermediate and inner lower tubings and registering with the first coupling means mentioned when said well fluid inlet is seated on said pump seat; and passage means formed in said coupling means for connecting said lower supply tubing in fluid communication with said upper supply tubing, said lower return tubing in fluid communication with said upper return tubing and said lower production tubing in fluid communication with said upper production tubing when said well fluid inlet is seated on said pump seat.

6. A fluid operated pumping system as set forth in claim wherein said one upper tubing and said outer lower tubing are said upper production tubing and said lower production tubing, respectively, wherein said intermediate lo-wer tubing is said lower return tubing and wherein said inner lower tubing is said lower supply tubing.

7. In combination: three upper tubings in side-by-side relation; three lower tubings in concentric relation below said upper tubings and aligned with one of said upper tubings; coupling means interconnecting the lower ends of said upper tubings and the upper end of the outermost of said lower tubings; another coupling means interconnecting the upper ends of the others of said lower tubings, said other coupling means and said others of said lower tubings being movable axially of said one upper tubing and the outermost of said lower tubings relative to a position wherein said other coupling means register with the coupling means first mentioned; and passage means formed in said coupling means for connecting said lower tubings to said upper tubings, respectively, in fluid communication therewith when said other coupling means and said others of said lower tubings are in said position.

8. in a fluid operated pumping system for a well, the

combination of: upper supply and production tubings set in the well in side-by-side relation, said upper production tubing being larger than said upper supply tubing;

a lower production tubing set in the well below and in alignment with said upper production tubing; first coupling means interconnecting the lower ends of said upper production and supply tubings and the upper end of said lower production tubing; a pump seat at the lower end of said lower production tubing and communicating with the well; a fluid operated pump assembly movable downwardly through said upper production tubing into said lower production tubing and having a fluid operated pump at its lower end, said pump having a well fluid inlet at its lower end which is seatable on said pump seat in fluid communication with the well, said pump assembly including a lower supply tubing disposed within and concentric with said lower production tubing when said well fluid inlet is seated on said pump seat; second coupling means connected to the upper end of said lower supply tubing and registering with said first coupling means when said well fluid inlet is seated on said pump seat; and passage means formed in said coupling means for connecting said lower supply tubing in fluid communication with said upper supply tubing and said lower production tubing in fluid communication with said upper production tubing when said well fluid inlet is seated on said pump seat.

9. A fluid operated pumping system as set forth in claim 8 wherein said pump is provided with an axial passage therethrough the upper end of which communicates with said lower supply tubing and the lower end of which communicates with the exterior of said pump above said pump seat when said well fluid inlet is seated on said pump seat, said pump including valve means normally closing said axial passage and including pressure responsive means communicating with the interior of said lower production tubing for opening said valve means.

10. In combination in a well having an upper zone of one diameter and a lower, bottom hole zone of a smaller diameter, the combination of: upper supply, return and production tubings set in said upper zone of said well in side-by-side relation and extending downwardly in. said upper zone substantially to the lower end thereof; concentric, lower supply, return and production tubings below said upper tubings and extending downwardly from the lower end of said upper zone of said well into said lower zone thereof; means providing a supply passage connecting said lower supply tubing in fluid communication with said upper supply tubing, a return passage connecting said lower return tubing in fluid communication with said upper return tubing, and a production passage connecting said lower production tubing in fluid communication with said upper production tubing; a fluid operated pump in the well below said upper tubings and adjacent the lower ends of said lower tubings and having an operating fluid intake in fluid communication with said lower supply tubing, a spent operating fluid exhaust in fluid communication with said lower return tubing and a production fluid outlet in fluid communication with said lower production tubing, said pump also having a well fluid inlet; and means connecting said well fluid inlet in fluid communication with the well.

References Cited in the file of this patent UNITED STATES PATENTS 2,311,157 Coberly Feb. 16, 1943 2,589,669 Coberly Mar. 18, 1952 2,676,546 Coberly Apr. 27, 1954 2,851,954 Coberly Sept. 16, 1958 FOREIGN PATENTS 62,878 Denmark Nov. 6, 1944 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,005Al4 October 24 1961 Clarence J. Coberly It is hereby certified that error appears in ;the

ent,requiringeorrection and. that the said Letters Pat "corrected below.

above riumbered patent should read as Column 9 line 4L8 for "register" read registers Signed and sealed this 10th day of April '1962.

(SEAL) Attest:

ERNESTW. SWIDER DAVID L. LADD Attesting Offioer Commissioner of Patents 

